function bigAdd(x, y) {
  let maxLen = Math.max(x.length, y.length);
  x = x.padStart(maxLen, 0);
  y = y.padStart(maxLen, 0);
  let i = maxLen - 1;
  let sum = [];
  let crray = 0;
  while (i > 0) {
    let tempx = parseInt(x.charAt(i));
    let tempy = parseInt(y.charAt(i));
    sum[i] = (tempx + tempy + carry) % 10;
    carry = (tempx + tempy + crray) / 10;
  }
  console.log(sum);
}
